Bump actions/cache from 4 to 5 (#1111)

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/RustNightly.yml

@@ -54,7 +54,7 @@ jobs:
       # rust-cache cleans "anything not a dependency" from target dirs, removing the sysroot.
       # We cache sysroot separately to avoid rebuilding it (~10s) on every run.
       - name: Sysroot cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             src/tests/rust_guests/simpleguest/target/sysroot

.github/workflows/dep_build_guests.yml

@@ -48,7 +48,7 @@ jobs:
       # rust-cache cleans "anything not a dependency" from target dirs, removing the sysroot.
       # We cache sysroot separately to avoid rebuilding it (~10s) on every run.
       - name: Sysroot cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             src/tests/rust_guests/simpleguest/target/sysroot

.github/workflows/dep_code_checks.yml

@@ -44,7 +44,7 @@ jobs:
       # rust-cache cleans "anything not a dependency" from target dirs, removing the sysroot.
       # We cache sysroot separately to avoid rebuilding it (~10s) on every run.
       - name: Sysroot cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             src/tests/rust_guests/simpleguest/target/sysroot
@@ -108,7 +108,7 @@ jobs:
       # rust-cache cleans "anything not a dependency" from target dirs, removing the sysroot.
       # We cache sysroot separately to avoid rebuilding it (~10s) on every run.
       - name: Sysroot cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             src/tests/rust_guests/simpleguest/target/sysroot